A campaign to criminalise men who pay for sex rather than prostitutes has hit the streets with an alarming billboard advert.

The public is being targeted in Dublin, Cork, Limerick, Sligo and Waterford as lobbyists raise awareness using the story of 14-year-old Anna who was forced into sex work.

Denise Charlton, chief executive of the Immigrant Council of Ireland which has helped spearhead the campaign, said all avenues need to be explored to raise awareness and force a law change.

"It is now vital that the campaign to end exploitation and human trafficking uses every possible opportunity to inform people about the issues involved," she said. "The story of Anna depicted on the billboards is in no way unique and reflects a reality which exists in every county in Ireland."

The Turn Off The Red Light Campaign cited Department of Justice figures for 2011 which show that eight children were trafficked into Ireland for sexual exploitation, with 15 detected in 2010.

The group is encouraging members of the public to show their support and voice their views on social media, with #AnnaWas14 being used on Twitter.

Ms Charlton said: "Public support is needed to bring about real change and we hope the billboard and Twitter campaign will motivate people to contact their local politicians and demand that the sex trade is shut down by making it illegal to pay for sex.

"The opportunity for change is now and if we let it slip by it may not re-occur for decades to come."

The billboard campaign coincides with an August 31 deadline for written submissions to the Dail Justice Committee on whether vice laws should be changed.

Turn Off The Red Light campaigns to end prostitution and sex trafficking in Ireland and is backed by more than 50 organisations including trade unions, political parties and rights groups. It wants to make Ireland's vice laws similar to Sweden where people who pay for sex are criminalised before the prostitute.